JP3087535B2 - Inkjet cartridge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet cartridge, and more particularly to an ink jet cartridge in which an ink tank and a print head for discharging ink in the ink tank are integrally mounted on a recording apparatus.

[0002]

2. Description of the Related Art Conventionally, as this type of ink jet cartridge, there is Japanese Patent Application Laid-Open No. 63-87242, in which ink is stored in a foam material packed in an ink tank, and the ink is stored in a cartridge by a capillary force generated by the foam material. The inside is maintained at a constant negative pressure to hold ink.

[0003]

The above-mentioned conventional ink jet cartridge has a drawback that the volume efficiency is poor and the amount of the ink is limited because the ink is stored in the foam material.

[0004]

This onset Ming Lee inkjet cartridge SUMMARY OF THE INVENTION is an ink jet cartridge for mounting to the recording apparatus so as to be integrated with the print head to eject ink in the ink tank and the ink tank,
A first method in which a liquid is confined by leaving a trace amount of gas inside a small chamber provided with a filter that allows gas to pass through but not liquid through the upper surface that contacts the gas inside the ink tank and the lower surface that contacts the gas outside the ink tank. leaving the pressure adjusting chamber, the interior of the chamber through the gas in each of the lower surface in contact with the gas inside the upper surface and the ink tank in contact with the ink tank outside the gas but the liquid that IF filter such threaded is provided a small amount of gas A second pressure adjusting chamber for confining the liquid, and in this configuration, the ink tank and the first and second pressure adjusting chambers are connected by a member generating a capillary force. Further, in this configuration, when the ink jet cartridge is placed in a state rotated by 90 degrees from the normal state, the above-mentioned condition is satisfied. Of the filter surface which one is in contact with the ink tank gas inside each of the gas left in the pressure regulating chamber, so that the filter surface of the other is in contact with the ink tank outside the gas, of the pressure adjusting chamber filter The opposite surface except the surface is configured to have a tapered shape.

[0005]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of one embodiment of the present invention.
The embodiment of FIG. 1 includes an ink tank 1 for storing ink 4,
It has a print head 3 for discharging ink 4 from an ink tank 1, and a negative pressure generator 2 composed of an A pressure adjustment chamber 6 and a B pressure adjustment chamber 7. Further, the negative pressure generating section 2 is made of a member that generates a capillary force so that the A pressure adjustment chamber 6 and the B pressure adjustment chamber 7 are not covered with ink regardless of how the ink jet cartridge is placed. It is connected to the ink tank 1 by an ink intrusion prevention wall 5.

FIG. 2 is a detailed view of the negative pressure generator 2. A pressure adjustment chamber 6 and B pressure adjustment chamber 7 in negative pressure generating section 2
In is the gas to each of the upper and the lower surface pass but liquid attached filter impervious, small amount of liquid 8 therein (pure water, etc.) are confined to leave air bubbles 9 traces structure Has become. The A pressure adjustment chamber 6 is mounted such that the filter 10 on the upper surface contacts the gas inside the ink tank 1 and the filter 11 on the lower surface contacts the gas outside the ink tank 1. The B pressure adjustment chamber 7 is mounted such that the filter 12 on the upper surface contacts the gas inside the ink tank 1 and the filter 13 on the lower surface contacts the gas inside the ink tank 1. The arrangement of the A pressure adjustment chamber 6 and the B pressure adjustment chamber 7 is not limited as long as they are mounted as described above.

FIG. 3 is a diagram for explaining the function of the pressure adjustment chamber using the A pressure adjustment chamber 6 as an example. As shown in FIG. 3A, the pressure of the gas applied around the A pressure adjustment chamber 6 is the pressure Pt of the internal gas in the ink tank 1, the pressure Pa of the external gas in the ink tank 1, and the pressure in the A pressure adjustment chamber 6. If the pressure ρgh (ρ: density of the liquid 8, g: gravitational acceleration, h: height of the liquid 8) by the weight of the liquid 8 is set, Pa = Pt + ρgh on the filter 11 surface. Therefore, when the ink is held, the ink is held in a negative pressure state satisfying Pt ≧ Pa−ρgh from Pa ≦ Pt + ρgh. Here, ink tank 1
If the pressure of the internal gas of A becomes larger than the pressure of the external gas of the ink tank 1, if the volume change in the A pressure adjustment chamber 6 does not occur, the state of FIG. No delivery of gas is performed. Further, the pressure of the gas inside the ink tank 1 decreases due to the consumption of the ink 4 at the time of ink ejection, and Pa> Pt + ρgh, that is, Pt
When it becomes <Pa-ρgh, the delivery of gas is performed as shown in FIG. 3B, and the excessive negative pressure is eliminated.

As described above, the A pressure regulating chamber 6 functions as a valve that allows gas to pass only in one direction. On the other hand, the B pressure adjustment chamber 7 has the same function as the A pressure adjustment chamber 6, but the direction in which gas passes through the A pressure adjustment chamber 6 is reversed.

FIG. 4 shows a negative pressure generating unit 2 at the time of ink ejection.
FIG. During ink holding, the pressure of the gas inside the ink tank 1 is maintained at a negative pressure within a value obtained by subtracting the pressure of the liquid 8 in the A pressure adjustment chamber 6 from the pressure of the gas outside the ink tank 1. 4 is retained. As shown in FIG. 4A, at the time of ink ejection,
The ink 4 in the ink tank 1 is consumed by being discharged from the print head 3, and the pressure of the gas inside the ink tank 1 decreases. The pressure is the ink tank 1
4 is smaller than the value obtained by subtracting the pressure due to the weight of the liquid 8 in the A pressure adjustment chamber 6 from the pressure of the external gas of FIG.
As shown in (b), the bubbles 9 in the A pressure adjustment chamber 6 are sent into the ink tank 1, and at the same time, the A pressure adjustment chamber 6
The external gas is sent into the A pressure adjusting chamber 6 by the amount of the bubbles 9 sent into the ink tank 1 from the nozzle. By repeating this operation, a constant negative pressure is maintained. At this time, gas is not delivered in the B pressure adjustment chamber 7 because the pressure applied state is opposite to that in the A pressure adjustment chamber 6.

FIG. 5 is a diagram showing the state of the negative pressure generating section 2 when the gas inside the ink tank 1 expands. The volume of the gas inside the ink tank 1 expands due to a change in the use environment such as a change in temperature or a rise in altitude, and the pressure of the gas inside the ink tank 1 increases. The pressure is the ink tank 1
5 becomes larger than the sum of the pressure of the liquid 8 in the A pressure regulating chamber 6 and the pressure of the liquid 8 in the A pressure regulating chamber 6 from the pressure of the external gas of FIG.
As shown in (b), the bubbles 9 in the B pressure adjustment chamber 7 are released to the outside of the ink tank 1, and at the same time, the amount of the ink tank 1 equal to the amount of the bubbles 9 released from the B pressure adjustment chamber 7 to the outside of the ink tank 1. Is sent into the B pressure adjustment chamber 7. By repeating this operation, the volume expansion of the gas inside the ink tank 1 is eliminated, and the ink tank 1 is returned to the state at the time of holding the ink. At this time, gas is not delivered in the A pressure adjustment chamber 6 because the pressure applied state is opposite to that in the B pressure adjustment chamber 7.

FIG. 6 is a sectional view of another embodiment of the present invention. In the embodiment of FIG. 6, the A pressure adjusting chamber 6 of the embodiment of FIG.
The cross-sectional shapes of the pressure adjusting chamber 7 and the pressure adjusting chamber 7 are changed to an A pressure adjusting chamber 16 and a B pressure adjusting chamber 17, respectively.

In the case of the sectional shape of the A pressure adjusting chamber 6 and the B pressure adjusting chamber 7 as shown in FIG. 1, when the cartridge is placed as shown in FIG. Both bubbles 9 in the pressure adjustment chamber 7 are
May come into contact only with the gas inside. In this case, even when the volume of the gas inside the ink tank 1 expands, the gas inside the ink tank 1 is not released to the outside of the ink tank 1, so that the ink leaks from the print head 3.

In view of this, the A pressure adjusting chamber 16 shown in FIG.
7 and FIG.
Even in the case of placing as shown in (b), one of the bubbles 9 in the A pressure adjustment chamber 16 and the B pressure adjustment chamber 17 is always one of the ink tanks 1.
Is in contact with the gas inside, and on the other hand, the ink tank 1 comes into contact with the gas outside.

[0015]

As described above, according to the present invention, since the negative pressure generating portion is provided inside the cartridge, the gas inside the cartridge can always be maintained at the negative pressure without using the foam material. There is an effect that more ink can be held in the same volume as compared with the method using a material.

[Brief description of the drawings]

FIG. 1 is a sectional view of one embodiment of the present invention.

FIG. 2 is a detailed view of a negative pressure generator of the embodiment of FIG.

FIG. 3 is a diagram for explaining a function of a pressure adjustment chamber in which the A pressure adjustment chamber of the embodiment in FIG. 1 is used as an example.

FIG. 4 is a diagram illustrating a state of a negative pressure generating unit during ink ejection according to the embodiment of FIG. 1;

FIG. 5 is a diagram showing a state of a negative pressure generating unit when the gas inside the ink tank of the embodiment of FIG. 1 expands.

FIG. 6 is a sectional view of another embodiment of the present invention.

7 is a diagram for comparing the functions of the embodiment of FIG. 1 and the embodiment of FIG. 6 according to the cross-sectional shapes of the A pressure adjustment chamber and the B pressure adjustment chamber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink tank 2 Negative pressure generation part 3 Print head 4 Ink 5 Ink intrusion prevention wall 6,16 A pressure regulation room 7,17 B pressure regulation room 8 Liquid 9 Bubbles 10,11, -13 Filter

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41J 2/175

Claims (3)

(57) [Claims] An ink jet cartridge in which an ink tank and a print head for ejecting ink in the ink tank are integrally attached to a recording apparatus, an upper surface in contact with gas inside the ink tank and a lower surface in contact with gas outside the ink tank. A first pressure regulating chamber in which a small amount of gas is left inside the small chamber provided with a filter through which gas passes but liquid does not pass, and a first pressure regulating chamber in which the liquid is confined; the gas in each of the lower surface in contact with gas through it and having a liquid leaving the inside traces of gas chambers which awe filter is provided such through the second pressure regulating chamber confined liquid inkjet Tsu Toto cartridge. 2. The ink-jet cartridge according to claim 1,
An ink cartridge, wherein the ink tank and the first and second pressure adjusting chambers are connected by a member generating a capillary force. 3. The ink jet cartridge according to claim 2, wherein one of the gases left inside each of the two pressure adjustment chambers even when the ink jet cartridge is rotated by 90 degrees from a normal state. Ink jets characterized in that the opposite faces of these pressure adjustment chambers except for the filter face are tapered so that the filter face is in contact with the gas inside the ink tank and the other is on the filter face in contact with the gas outside the ink tank. cartridge.